Habib, S. (2022). Leishmania donovani promotes macrophages polarization towards M2 phenotype in vitro: A new approach to identify a new therapeutic target. Parasitologists United Journal, 15(3), 274-282. doi: 10.21608/puj.2022.155256.1182
Samar Habib. "Leishmania donovani promotes macrophages polarization towards M2 phenotype in vitro: A new approach to identify a new therapeutic target". Parasitologists United Journal, 15, 3, 2022, 274-282. doi: 10.21608/puj.2022.155256.1182
Habib, S. (2022). 'Leishmania donovani promotes macrophages polarization towards M2 phenotype in vitro: A new approach to identify a new therapeutic target', Parasitologists United Journal, 15(3), pp. 274-282. doi: 10.21608/puj.2022.155256.1182
Habib, S. Leishmania donovani promotes macrophages polarization towards M2 phenotype in vitro: A new approach to identify a new therapeutic target. Parasitologists United Journal, 2022; 15(3): 274-282. doi: 10.21608/puj.2022.155256.1182
Leishmania donovani promotes macrophages polarization towards M2 phenotype in vitro: A new approach to identify a new therapeutic target
Department of Medical Parasitology, Mansoura Faculty of Medicine, Mansoura University,Mansoura, Egypt & Medical College of Georgia (MCG), Augusta University, Augusta, GA, USA
Abstract
Background: The immune response against L. donovani depends significantly on infected macrophages. Since Leishmania amastigotes deploy several immune suppressive mechanisms to escape host immune responses, macrophages polarize towards the classically activated macrophages (M1) or the alternatively activated macrophages (M2). The balance between both types is crucial in shaping the infection outcome. Objective: The aim of this study is to explore the macrophage polarization behavior in response to L. donovani infection, and to examine the differential expression of IL-10 and TNF-α by each phenotype. Material and Methods: Leishmania-infected phorbol 12-myristate 13-acetate (PMA)-treated human leukemia monocytic cell line (THP-1) was used as an in vitro model of Leishmania infection. Leishmania stationary phase promastigotes were used to infect the macrophages at different multiplicities of infections (MOIs) i.e., ratio of macrophages to stationary phase promastigotes at 1:1, 1:10, and 1:20; and time points of 24 and 48 h post infection (PI). While CD68, CD40, HLA-DR were used as markers for M1; CD68 and CD163 were used to characterize M2. Both M1 and M2 phenotypes were analyzed using flow cytometry. To evaluate the behavior of polarization, IL-10 and TNF-α were tested in both phenotypes, in addition to the assessment of percentage of infected macrophages. Results: The percentage of M1 exhibited significant decrease followed by non-significant increase, while M2 showed significant increase correlating with the MOIs. Both phenotypes expressed MOI-dependent increase in IL-10, but only M1 significantly expressed TNF-α. Besides, M2 phenotype predominated M1, in a time and MOI dependent manner. Conclusion: Leishmania infection induces macrophages polarization towards M2, with significant production of IL-10. These results extend knowledge regarding the immunomodulation exerted by Leishmania amastigotes to defeat the immune system.